Wheel-unit-ready ski for ski-mounted vehicle

ABSTRACT

A snowmobile ski adapted to accommodate wheel units that are movable between a deployed position and a stowed position. The floor of the ski has one or more wheel openings to allow wheels to drop down to the deployed position. A wheel unit may have a single wheel or two wheels in tandem. The wheel units may be mounted on the kingpin, the side wall, inner ribs, or on the steering spindle.

BACKGROUND INFORMATION

1. Field of the Invention

The invention relates to the field of snowmobiles. More particularly,the invention relates to skis for snowmobiles or other ski-mountedvehicles, with selectively deployable wheel units.

2. Description of the Prior Art

Snowmobiles are vehicles that are constructed to travel across snow andice. As is generally known, the snowmobile is driven by an endless drivetrack arranged at the rear end of the underside of the snowmobile. Thefront end of the snowmobile is supported on two skis, which glide acrossthe surface of the snow or ice. The skis typically have a carbide runnerthat runs along a portion of the bottom surfaces, to help keep thesnowmobile traveling along a smooth track.

A disadvantage of snowmobiles is that the skis don't readily glideacross gravel, hardtop, or other non-snow surfaces. It is difficult, ifnot impossible, to maneuver a snowmobile across a roadway, driveway,onto a ferry, etc., because the skis do not respond properly to steeringoperations initiated at the handlebars. Quite often, the snowmobileneeds to be dragged or pushed on driveways and across roadways, etc.Furthermore, driving or dragging a snowmobile across a non-snow surfacecauses excessive wear on the carbide runners, which then need to bereplaced.

In recent years, the sport of snowmobiling has evolved from one oftraveling relatively short distances over trails close to home to one ofweekend-long or longer cross-country trips. Previously, for example, asnowmobile operator would fill the gasoline tank of the snowmobile inhis or her backyard, transport the snowmobile to a trail site or departdirectly from the backyard for an afternoon or day of travel oversnowmobile club trails, and then return home. Nowadays, people aretraveling great distances across country on snowmobiles that involvetwo- or three-day tours or even such mammoth tours as from Alaska toMaine. Thus, where in the past the tank on the snowmobile was filled athome or at the point of departure before a daylong excursion,snowmobiles now need to be refilled while out traveling. This means thatthe snowmobile must be driven to a service station, typically bytraveling some distance along a surface other than snow or ice, forexample, along an asphalt road or gravel road. Also, it is notguaranteed for such lengthy trips that snow will always be available asa travel surface and, consequently, snowmobiles more and more frequentlyneed to travel some distance across asphalt or gravel surfaces. When asnowmobile needs to be dragged or pushed only a short distance across aroadway or driveway, or up a ramp onto a ferry or trailer, it ispossible for a person to do it alone or with the assistance of atraveling companion. Now, however, with the need to travel several milesalong a roadway to get to a filling station, the inability to steer asnowmobile has become a major obstacle in the logistics and theenjoyment of the sport.

Efforts to make snowmobiles mobile on gravel or other surfaces have beenundertaken over the years. Prior art includes conversion kits to replacethe skis with wheels. These conversion kits were intended to replace theskis on a semi-permanent basis, that is, to convert a snowmobile into awheeled vehicle for an extended period of time. Such conversion kitstypically require that the ski be removed in order to mount the wheels,or, if the ski does remain attached to the vehicle, a longer kingpinmust be used to mount the wheels. Thus, each time the wheels are mountedor removed, the kingpin must be replaced with the longer or shorter one,respectively. Both methods of converting the snowmobile to a wheeledvehicle involve a fair amount of work. Thus, such conversion kits arenot generally an acceptable solution to the problem of having to changein relatively quick succession back and forth between a vehicle thatrides on skis and one that rides on wheels, as happens when travelingover gravel or hardtop to fill the gas tank or to load onto a ferry ortrailer.

The inventor of the present invention is also the inventor of severalpatents for wheel units for snowmobiles, all of which are incorporatedherein in their entirety by reference: U.S. Pat. No. 6,527,282, issued 4Mar. 2003; U.S. Pat. No. 6,824,147, issued 30 Nov. 2005; and U.S. Pat.No. 6,932,359, issued 23 Aug. 2005. In the meantime, innovation anddevelopment has also continued on the snowmobiles themselves. Today,modern snowmobiles have many more comforts and features than earliermodels, and because of that, are also much heavier, and, in some cases,have become so heavy that more rugged and robust wheel units are needed.

What is needed therefore is simple and effective method of equipping asnowmobile with a wheel unit.

BRIEF SUMMARY OF THE INVENTION

The invention is a system of modular assemblies related to mounting andoperating a wheel unit on a ski, whereby the ski is adapted to receivethe modular assemblies. The inventive ski is referred to hereinafter asthe “wheel-unit ready ski.” By “modular assembly” is meant an assemblythat may be mounted in or on a ski, either as an after-market add-on orby the manufacturer as a purchase option. Examples of the modularassemblies are various types of wheel units and various types ofwheel-unit deployment assemblies, which may be mounted on the kingpin ora side wall of the wheel-unit ready ski or on a steering spindle thatcouples to the kingpin. The wheel units include single-wheel units andtandem-wheel units, and the deployment means include manual,semi-automated, and automated deployment means.

The inventive concept allows the purchaser or operator of a snowmobileor other type of vehicle with skis to choose among various wheel-unitoptions. Reference may be made hereinafter to a “snowmobile ski,”because that is the most common type of vehicle with skis, but it isunderstood, that other types of vehicles, such as recreational vehicles,may be equipped with skis and skis with wheel units and such skis andwheel units are included in the scope of the invention.

The wheel-unit ready ski according to the invention is a moldedcomponent that has certain conventional structural elements, such asside walls, a portion of which are reinforced to support a boss forholding and supporting a kingpin and kingpin bushing, inner ribs, and abottom glide surface. Other than that, the wheel-unit ready ski is notlimited to any particular configuration with regard to placement ofrunners, carbides, etc. The wheel-unit ready ski is constructed so as tobe able to receive the modular assemblies. For example, the inner ribsmay have pre-drilled bores and/or brackets for mounting the modularassemblies, thus eliminating the work of measuring, aligning, anddrilling holes later on for mounting the assemblies. Certain mountingelements for the modular assemblies may be integrated into the mold ofthe ski, so that the ski is adapted to receive a wheel unit and adeployment means, without having to modify the molded wheel-unit readyski. The ski may be molded from a variety of materials, such as, but notlimited to, plastic, a metal or metal alloy, carbon fiber, etc., and maybe a saddled or saddleless ski, the saddle being a metal U-shaped orL-shaped channel that is provided in a central portion of the ski,between the ribs.

A snowmobile ski is a construction that is carefully balanced about anaxis provided by the kingpin. This kingpin axis, also referred tohereinafter as the balance point, provides the ideal mounting point fora wheel unit. For this reason, in one embodiment of the invention, oneor two wheel unit assemblies are mounted on or about the kingpin. Thewheel or wheels of the wheel unit may extend beyond the body of thewheel-unit ready ski, i.e., be outside-mounted wheels. There are anumber of reasons, however, that make it desirable to have the wheelsmounted within the side walls of the wheel-unit ready ski. An insidemounting reduces the likelihood that the wheels will hit rocks orstumps, eliminates snow spray up onto the snowmobile rider or operator,and reduces stress on the kingpin. The wheel-unit ready ski according tothe invention is a pre-molded ski body with one or more wheel openingsfor allowing the wheels to drop down or to be pulled up from the rollingsurface. Also, a mounting means or bracket may be incorporated into themolded ski, to allow a manual or an automated deployment means to beeasily fitted to the ski and the selected wheel unit.

A second embodiment of the invention includes the wheel-unit ready skidescribed above with the wheel unit mounted on the snowmobile steeringspindle. The conventional snowmobile steering spindle may be used as isor may be adapted to accommodate a particular configuration of wheelunit and deployment means. The snowmobile steering spindle is mounted onthe A-arms or stabilizing arms of the snowmobile and movably coupledwith the kingpin. This spindle body has a boss on each side with athrough-bore extending through the bosses for receiving the kingpin.Typically, a kingpin bushing extends through the two through-bores andthe bosses. The kingpin is inserted through the bushing of the spindleand through the side walls of the ski. The spindle bosses themselves orthe kingpin bushing provide another suitable location for mounting themodular wheel unit assemblies, because these elements, too, are balancedabout the kingpin. Thus, a wheel unit mounted on the spindle bosses orbushing is also mounted indirectly on the kingpin. The steering spindleis conventionally cast from metal. Ideally, a steering spindle accordingto the invention has integrated into the casting a bracket or handle forcoupling the spindle with a deployment means for the wheel unit.

In addition to the modular assemblies mentioned above, the wheel-unitready ski according to the invention may also have additional features,such as a fender for outside mounted wheel units or a snow guard forinside mounted wheel units, to prevent snow from flying up through thewheel openings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is described with reference to the accompanyingdrawings. In the drawings, like reference numbers indicate identical orfunctionally similar elements. The drawings are not drawn to scale.

FIG. 1A is a top plan view of the first embodiment of the wheel-unitready ski according to the invention, showing wheel openings in thefloor of the ski, inside the side wall.

FIG. 1B is a top plane view of the second embodiment of the wheel-unitready ski according to the invention, showing a bulge in the side wallin the area of the kingpin.

FIG. 1C is a top plan view of the third embodiment of the wheel-unitready ski according to the invention, showing a widened area outside ofthe side wall, with wheel openings in the widened area, for an outsidemount.

FIG. 1D is a top plan view of the fourth embodiment of the wheel-unitready ski according to the invention, showing a saddle and wheelopenings for an inside mount.

FIG. 2 is a side elevation view of the ski of FIG. 1A.

FIG. 3 is a side elevation view of two wheel units ganged together by acoupling assembly that is coupled to a manual deployment means.

FIG. 4 is a top plan view of the wheel units and coupling assembly ofFIG. 3.

FIG. 5 illustrates the single-wheel unit outside mount, mounted on thekingpin, with means for assembling a manual deployment means and anautomated deployment means on the ski.

FIG. 6A illustrates the first tandem-wheel unit with the wheels moved tothe stowed state, each wheel mounted on a separate cam plate.

FIG. 6B illustrates the first tandem-wheel unit of FIG. 6A, with thewheels moved to the deployed state.

FIG. 7A illustrates a second embodiment of the tandem-wheel unit, withthe wheels moved to the stowed state, the two wheel units gangedtogether and coupled to a single cam plate.

FIG. 7B is an illustration of the tandem-wheel unit of FIG. 7A, moved tothe deployed state.

FIG. 8A an inside-mounted single-wheel wheel unit, with the wheeldeployed through a wheel opening in the ski floor.

FIG. 8B shows an outside-mounted tandem-wheel unit, with a single camplate mounted on the kingpin and the two wheels coupled together.

FIG. 8C shows an inside-mounted tandem-wheel unit, with the cam plate ofone wheel mounted on the kingpin and the cam plate of the second wheelunit coupled to the first cam plate.

FIG. 8D illustrates a second tandem-wheel unit in the stowed position,both wheels mounted on a guide and the guide coupled to a cam plate thatis mounted on the kingpin.

FIG. 8E illustrates a side wall with bushings for mounting one or morewheel units.

FIG. 8F shows a cam plate with a stub shaft for mounting a wheel unit inone of the bushings.

FIG. 9 is a perspective view of the manual deployment means.

FIG. 9A is a top plan view of the manual deployment means of FIG. 12.

FIG. 9B is a side elevation view of the manual deployment means

FIG. 9C is a front elevation view of the manual deployment means.

FIG. 9D is a rear elevation view of the manual deployment means.

FIG. 9E is an exploded view of the actuating lever with the lockinghandle.

FIG. 9F is a front elevational view of the actuating lever.

FIG. 9G is a side elevational view of the actuation lever.

FIG. 10 illustrates the automatically actuated deployment means mountedin the wheel-unit ready ski.

FIG. 11A is a side elevation view of the semi-automatically actuateddeployment means, with the wheel unit in the stowed position.

FIG. 11B is a side elevation view of the semi-automatically actuateddeployment means, with the wheel unit in the deployed position.

FIG. 12A is a rear elevation view of a conventional snowmobile steeringspindle. (prior art)

FIG. 12B is a side elevation view of the conventional snowmobilesteering spindle of FIG. 12A. (prior art)

FIG. 13 is a side elevation view of the steering spindle according tothe invention, showing a deployment means guide extending from a lowerend of the spindle.

FIG. 14 is a rear view of the steering spindle according to theinvention, showing a bracket for coupling the steering spindle with thedeployment means and wheel units mounted on the spindle boss.

FIG. 15 illustrates the automatic deployment means anchored at thetrailing end of the ski, with the rod of the automatic deployment meansextending through a through-hole in the steering spindle and coupledwith the cam plate of a wheel unit.

FIG. 16 illustrates the automatic deployment means anchored at theleading end of the ski, with the rod coupled to the cam plate of a wheelunit.

FIG. 17 illustrates the wheel unit mounted on an extended spindlebushing.

FIG. 18 illustrates the piston connected to the cam plate.

FIG. 19 illustrates a fender on the wheel-unit ready ski.

FIG. 20 illustrates a cylinder incorporated into the spindle body of thesteering spindle.

FIG. 21 illustrates through-bores in a saddle for mounting a wheel unitand receiving the kingpin.

FIG. 22A is a schematic illustration, showing the cross-section of afull saddle with a kingpin passing through the through-bores.

FIG. 22B is a schematic illustration, showing the cross-section of ahalf-saddle with a kingpin passing through a through-bore.

FIG. 22B illustrates through-bores in the half-saddle for mounting awheel unit and for the kingpin.

DETAILED DESCRIPTION OF THE INVENTION

The present invention will now be described more fully in detail withreference to the accompanying drawings, in which the preferredembodiments of the invention are shown. This invention should not,however, be construed as limited to the embodiments set forth herein;rather, they are provided so that this disclosure will be complete andwill fully convey the scope of the invention to those skilled in theart.

FIGS. 1A-1D illustrate various embodiments of a wheel-unit ready ski1000 according to the invention, adapted to receive a wheel unit 200 anda deployment means 400 that may be provided as modular assemblies thatare assembled on the ski post purchase or are incorporated into aready-to-sell ski. Various embodiments of the wheel unit 200 anddeployment means 400 are shown in FIGS. 3-8F and FIGS. 9-11B,respectively, and will be discussed below. FIGS. 1A-1D show thewheel-unit ready ski as a saddleless ski, whereas, in FIG. 1D, thewheel-unit ready ski 1000 has a saddle or a shoe 150.

The terms 1000A-1000C shall designate specific embodiments of thewheel-unit ready ski 1000 and the term “wheel-unit ready ski 1000” shallrefer in general to a ski that has elements common to the variousembodiments of wheel units and deployment means. Reference is made toFIG. 1A and FIG. 2 to illustrate the basic features of the wheel-unitready ski 1000.

FIG. 1A is a top plan view and FIG. 2 a side elevation view of the firstembodiment 1000A of the wheel-unit ready ski 1000. The ski 1000 has aski body 100 that is a molded, pressed, or stamped component. The skibody 100 has a leading end 101 and a trailing end 102, two side walls104 extending upward from a ski floor 107, and a bottom surface that isthe ski glide surface. Whenever reference is made hereinafter to “front”or “rear” views of the various components and assemblies, “front” refersto the view when facing the leading edge 101 and “rear” the view whenfacing the trailing edge 102. A kingpin 110 extends across the ski body100 and is supported in through-bores in a reinforced section 104A ofthe two side walls 104. Not shown, but understood by those skilled inthe art, a kingpin bushing is inserted in the through-bores and thekingpin 110 inserted through the bushing. The reinforced section 104A isdimensioned to accommodate the various wheel unit installations and,thus, may extend over a greater length than shown in the illustrations.In the saddleless skis 1000A-1000C, a pair of reinforcing ribs 140 areprovided inside the side walls 104. The typical ski body also has twoinner ribs that extend parallel to a centerline along the greaterportion of the ski. These inner ribs may also be reinforced, as will bediscussed in connection with FIG. 8E.

The wheel-unit ready ski 1000 has a wheel opening 120 in the ski floor107 that is dimensioned to allow the wheel unit 200 to be deployed,i.e., to lower a wheel into contact with a road or floor surface. FIGS.1A-1D show wheel openings 120 on both sides of the ski body 100. It isunderstood, however, that all of the wheel-unit ready skis 1000 may havea wheel opening 120 on one side only, depending on the type and intendeduse of the snowmobile.

FIG. 1A illustrates the first embodiment wheel-unit ready ski 1000A thatis adapted to accommodate two single-wheel wheel units 200, one on eachside of the ski. The wheel opening 120 is shown on one side as anuncovered opening and, on the other side, covered with a snow guard 600.This is for purposes of illustration only. If a wheel-unit ready ski1000 according to the invention is equipped with the snow guard 600, allwheel openings 120 will likely be fitted with the snow guard. FIG. 1Bshows the second embodiment of the wheel-unit ready ski 1000B that issimilar in construction to that of the first embodiment, but which has awidened area 100A in the ski body 100. This widened area is a designchoice that may be governed by the type of wheel unit the ski isintended to accommodate, or by aesthetics, etc. It is also understoodthat, instead of the widened area 100A that is constructed as apronounced bulge, the floor 107 of the ski body 100 may be widened alonga greater portion of the length of the ski. In other words, the outercontour of the ski body 100 may be gently curved to achieve the desiredwidened area 100A or may have a generally rectangular shape, as shown inFIG. 1A, but be wider along the length of the ski body. FIG. 1Cillustrates the third embodiment of the wheel-unit ready ski 1000C, inwhich the wheel opening 120 is provided outside of the sidewall 104, butthrough the floor 107 of the ski body 100. The wheel-unit ready ski1000A-1000C shown in the previous figures is a saddleless ski. FIG. 1Dillustrates the wheel-unit ready ski 1000 that has a shoe or saddle 150.In the embodiment shown, the saddle is a full saddle that fits insidethe sidewalls 104 and that is essentially an open metal channel withshallow sidewalls 152 that serve as the inner ribs 140 in themid-section of the ski body 100. The kingpin 110 passes through theshallow sidewalls, as well as through the sidewalls 104 on the ski body100. In the embodiment shown, the ski body has a widened area in thereinforced section, but it is understood that the ski may just as wellhave any shape that is suitable to accommodate the specific type ofwheel unit. Instead of the full saddle 150, a half-saddle 151 may alsobe used. FIGS. 21-22B illustrate cross-sectional and side views of thefull saddle 150 and the half-saddle 151.

All of the skis 1000A-1000D are constructed to receive the wheel unit200 and the deployment means 400 as modular assemblies, in order toprovide the vehicle owner with a number of options regardinginstallation of a wheel unit and a deployment means. FIGS. 3-7illustrate various embodiments of the wheel unit 200, each one coupledwith a manual deployment means 400A

FIG. 3 illustrates the basic components of a first wheel unit 200A thatmay be coupled to the kingpin, the wheel unit including a wheel 230mounted on a cam plate 212. One of the reasons for using the kingpin 110as a mount for a wheel unit is that the ski 1000 is balanced about thekingpin and it is, thus, the ideal position for mounting a wheel unit. Afirst position on the cam plate has a stub axle 216 for mounting a wheel230, a second position a coupling means 218 for coupling the cam plate212 to the deployment means 400 or, if two wheels 230 are to be yokedtogether, to a coupler 300, and a third position has a reinforced bore214 for coupling the cam plate with the kingpin 110, or to a guide ormounting plate that is incorporated into or mounted on the wheel-unitready ski 1000, or mounted on the side wall 104 of the wheel-unit readyski. FIGS. 3 and 4 show the wheel 230 mounted to the inside of the camplate 212. This configuration of the wheel unit 200A allows the unit tobe fitted onto wheel-unit ready skis 1000 that have wheel openings 120inside the side walls.

FIG. 4 also shows one example of a coupling linkage or assembly 300 thatmay be used to gang two wheel units together. In this case, twosingle-wheel units 200A are shown yoked together, with the wheels 230mounted on the inside surface of the cam plates 212. The coupler 300 hasa frame comprising a first link 310 that is coupled with a second link320 and with a yoke 312. An actuating lever 420 of the deployment means400 is coupled with the yoke 312. One end of the second link 320 iscoupled to the coupling means 218 on the cam plate 212. Depending on theexact configuration of the wheel-unit ready ski 1000 and the coupler300, bushings may be used to keep the actuating lever 420 properlycentered on the coupling bar 312. It is understood, that any of thewheel units described hereafter may also be coupled together in thismanner, regardless of how the wheel unit 200 is mounted on thewheel-unit ready ski 1000, whether on the kingpin, the side wall, or, aswill be discussed later, on a snowmobile steering spindle. Furthermore,the wheels 230 may be mounted on the outside of the cam plate 212 for anoutside mount.

FIG. 5 shows the wheel 230 mounted on the outside face of the cam plate212 and the cam plate mounted on the outside of the side wall 104. Inthis configuration, the wheel 230 drops down into a wheel opening 120that is provided on the area of the ski floor outside the side wall 104.Also illustrated is a ski 1000 that is adapted to receive a manualdeployment means 400A or an automated deployment means 400B. Elements ofthese deployment means 400A and 400B are described below in detail. Adeployment guide 410 and a bracket 130 are either integrated into ormounted on the molded ski body 100. With this wheel-unit ready ski 1000,the owner can choose to install either the manually operated deploymentmeans 400A or the automated one 400B. Most snowmobile operators orowners will elect one type of deployment means 400, but some may chooseto mount both types onto one ski, for example, when using the snowmobilein particularly harsh environments, to have a redundancy. FIG. 5 showsthat a manual and an automated deployment means may be mounted at thesame time on the wheel-unit ready ski 1000. The shift lever 420 on themanual system shown in this figure is adapted for use with the couplinglink 312 on the coupling assembly 300 that is shown in FIGS. 3 and 4. Ifthe wheel unit 200 is to be mounted on only one side of the ski 1000,the coupling mechanism 300 is eliminated and, when using the manuallyoperated deployment means 400A, the second end 424 of the shift lever420 couples directly to the coupling link 216 on the cam plate 212. Whenusing the automated deployment means 400B, the cylinder 442 is coupledto the bracket 130 and the rod 440 to the coupling link 216.

FIGS. 6A-6B are side elevation views of a first tandem-wheel unit 200B,with each wheel 230 mounted on a separate cam plate 212 and the two camplates 212 mounted on a rigid bar 213. For purposes of clarity, thesefigures illustrate details of the deployment means 400 and tandem-wheelunit without showing any features of the wheel-unit ready ski 1000. Itis understood that the rigid bar 213 may be mounted on the kingpin 110or on the side wall 104, either as an inside mount or an outside mount.A single deployment means 400 is coupled to the rigid bar 213, such thatthe deployment means moves both wheel units simultaneously between astowed position, shown in FIG. 6A, and a deployed position, shown inFIG. 6B. In this embodiment, one of the cam plates 212 is mounted eitheron the kingpin 110 or on the side wall of the wheel-unit ready ski.

FIGS. 7A and 7B illustrate a second embodiment of the tandem-wheel unit200C, in which the two wheels 230 are mounted on a rigid bar 213 and therigid bar movably coupled to a single cam plate 212. The rigid bar 213in this embodiment also serves as a rocker bar that allows the wheels torock up and down as the ski travels over uneven ground. Mounting the camplate on the kingpin 110 as shown places the wheels 230 equidistant fromthe kingpin 110, which maintains the desirable balance point on the ski.An actuating arm 420 from the deployment means 400 is coupled to the camplate 212. When the deployment means forces this bar 213 to move in afirst direction, the wheels 230 are brought to a deployed position,shown in FIG. 7B, and when forced to move in the opposite direction, thewheels 230 are brought to the stow position, shown in FIG. 7A. The camplate 212 is shown coupled to a coupling mechanism 300 in FIGS. 7A-7B.This is done if two sets of tandem-wheel units are used, one on eachside of the ski, to yoke them together. If only a single tandem-wheelunit is to be incorporated into the wheel-unit ready ski 1000, then thecoupling assembly 300 is not needed and instead, the coupling means 218on the cam plate 212 is coupled directly with the end of the actuatingarm 420.

FIGS. 8A-8F illustrate various configurations of wheel mounts for thevarious embodiments of the wheel units. FIG. 8A shows the single-wheelwheel unit 200A mounted on the kingpin 110 on the wheel-unit ready ski1000A. FIG. 8B illustrates an outside mounted tandem-wheel unit 200C,with the wheels deployed outside of the ski floor 107. FIG. 8Cillustrates the wheel unit 200B, with one wheel 230 mounted on thekingpin 110 and the second wheel 230 coupled with the first wheel by arigid bar. Whether the second wheel is in front of or behind thekingpin-mounted wheel is a design choice, depending on where themanufacturer prefers to have the wheel openings 120. Both embodimentsare within the scope of the invention. FIG. 8D illustrates thetandem-wheel unit 200C mounted directly to the side wall 104, by meansof a through-bore and insert. The sidewall 104 of the wheel-unit readyski 1000 has a reinforced section 104B that includes the bore for thekingpin 110. This reinforced section 104A extends to each side from thekingpin. One or more bores 113 or other fastening means may be providedin this reinforced section 104B and a stub axle provided on the camplate 212, for securing the cam plate to the side wall. FIG. 8E is a topplan view of the wheel-unit ready ski 1000, showing a plurality ofbushings 219 and FIG. 8F a top plan view of an adapted cam plate 212,showing the stub shaft 220. This particular wheel-unit ready ski 1000has been constructed to receive one or two wheel units 200 on one orboth sides of the ski. Appropriately, the reinforced section 104B onthis side of the ski is extended, to accommodate the additional inserts219. The wheel unit 200 is mounted on the wheel-unit ready ski 1000 byassembling the stub shaft 220 in the bushing 219 and securing it. Manytypes of fastening means are suitable to secure the stub shaft to theinsert, such as threaded fasteners, bolts, pins, etc. Also, in theembodiment shown, the bores 113 extend through the side wall. It is, ofcourse, also possible for the bore 113 to extend only partially throughthe side wall. This figure also illustrates a ski body 100 in which theinner ribs 104C have been made thicker or reinforced, so that thebushings may be mounted in the inner ribs, if so desired, rather than inthe reinforced section 104B.

The deployment means 400 according to the invention may be a manuallyactuated deployment means 400A, an automatically actuated deploymentmeans 400B, or a semi-automatic deployment means 400C. FIGS. 9-9Gillustrate the manually actuated deployment means 400A, which comprisesa guide 410, an actuating or shift lever 420 that is coupled to theguide, and a handle or grip 430. In the embodiment shown, the guide 410is a rail having a first end 411 and a second end 412 and a slot 416,but other embodiments of guides are within the scope of the invention.FIGS. 9 and 9B show a first lock position 414 and a second lock position415 on the slot. The actuating lever 420 has a first end 422 that isattached to the handle 430 and a second end 424 that is coupled to thecam plate 212 at the coupling means 218, or, if two wheel units areyoked together, coupled to the coupler 300. In the embodiment shown, thehandle 430 includes a spring-biased locking mechanism 432 that iscaptured in the slot 412 and holds the shift lever 420 locked into placeat each of the locking positions 414 and 415. When the handle 430 ispulled out from the guide 410, the handle may then be slid along theslot 412 to move to the other position. FIG. 9 shows the handle 430locked at the second lock position 415, thereby pulling the wheel unit200 to a stowed position S, in which the wheel 230 is raised above therolling surface. FIG. 9B shows the handle 430 locked at the first lockposition 414, in which the shift lever 420 pushes the cam 212 to adeployed position D, to lower the wheel 230 to the ground, floor, orother support surface. FIG. 9E illustrates details of the locking handle430. A coupling post 426 is provided on the shift lever 420, forcoupling with the cam plate at 218.

The guide 410 of the deployment means 400A is shown in FIGS. 9-9B as aseparate component that is mountable to the inner rib 140. A series ofmounting bores 428 may be provided in the guide 410 for this purpose. Itis understood, however, that the guide 410 may comprise a reinforcedsection that is integrated into the rib 140 when the wheel-unit readyski 1000 is molded, may be a separate metal component that is fastenedto the molded rib 140, or may be placed in the mold during the moldingprocess, so as to embed the component in the rib 140.

FIG. 10 shows the automatically actuated deployment means 400B mountedin the wheel-unit ready ski 1000. In this embodiment, the deploymentmeans is a fluid-driven, i.e., pneumatically or hydraulically operated,drive unit comprising a cylinder 442 and a rod 444. This type ofactuator is well known in many industries. Thus, the details regardingthe drive means for the deployment means are not shown. It isunderstood, that a switch is provided on the control panel of thevehicle, so that the operator may actuate the deployment means whileseated on the vehicle. The fixed end of the cylinder 442 is anchored tothe bracket 130 on the ski body 100 and the operative end of the rod 444is linked to the coupler 300, if one is used, or, if only one wheel unitis used, to the cam plate coupling means 218, as shown. Theautomatically actuated deployment means 400B is shown anchored at theleading end of the wheel-unit ready ski 1000. It can just as well beanchored to the trailing end. This is a design choice of the skimanufacturer.

FIGS. 11A and 11B illustrate the semi-automatic deployment means 400C. Aretraction spring 440, such as a helical coil spring, is schematicallydepicted and shown coupled to the shift lever 420, which is, in turn,coupled to the coupler 300 or the cam plate coupling means 218, as thecase may be. The retraction spring 440 may also be a coiled, wind-upspring that is coupled directly to the cam plate 212. The variouspossible constructions of a biasing spring are well-known in themechanical arts and these two types of retraction spring are provided assuggestions only. This spring biases the deployment means to move thewheel unit to the stowed position. Structurally, the semi-automaticdeployment means 400C is similar in concept to the manual deploymentmeans 400A, except that the retraction spring 440 snaps the actuatinglever 420 back to the stowed position S, when weight is lifted from theski. The particular construction of the first and second lock positionsin the guide 410 to accommodate the locking handle 430 that is used forthe manual deployment means 400A may be eliminated, because the weightof the ski holds the shift lever 420 in the deployed position and thebiasing spring moves it to the stowed position. The user of thesnowmobile must intentionally shift a knob or handle 421 captured inslot 412 from the stowed position 415 to the deployed position 414, inorder to deploy the wheels 230. As soon as the snowmobile travels backonto snow, weight is lifted from the ski and the retraction spring 440pulls the shift lever 420 back to the stowed position 415.

The wheel unit 200 is shown in the previously discussed figures mountedon the kingpin 110 or on the side wall 104 near the kingpin. Asmentioned above, mounting the wheel unit 200 on or balanced about thekingpin 110 is desirable, because the ski 1000 is balanced about thataxis. It is also possible, however, to mount the wheel unit 200indirectly to the kingpin 110 by mounting it directly on the steeringspindle that is coupled with the kingpin, as described below.

FIG. 12A is a front elevation view and FIG. 12B a side elevation view ofa conventional steering spindle, which is mounted on the A-arms orstabilizing arms of the vehicle. The A-arms are not shown, becausemounting the steering spindle on the stabilizing arms is conventionalpractice and well understood. The steering spindle has a spindle body Aand a boss B that provides a through-bore for the kingpin 110. A bushingis conventionally inserted through the through-bores to reinforce thesupport for the kingpin 110 and a washer and nut are used to secure thekingpin 110 to the spindle body A. The kingpin extends on both endsthrough the side walls of the ski. These figures show the conventionalsnowmobile steering spindle with the kingpin through the boss B. Theside wall 104 of the wheel-unit ready ski 1000 is indicated with dashedlines.

FIGS. 13-17 show various embodiments of a steering spindle 500 accordingto the invention that has been adapted to be couplable with any of thewheel units 200 and deployment means 400 described above. The lower endof the spindle body 510 has a first extension 512 that typically facesthe trailing end of the ski and a second extension 514 that faces theleading edge.

FIGS. 13 and 14 illustrate a first adaptation of the steering spindle500 according to the invention, showing the guide 410 of the deploymentmeans 400A or 400B extending from the first extension 512. The actuatinglever 420 is then couplable with the guide 410 and the wheel unit 200,as described above. A bracket 520 is provided on the first extension 512that serves to anchor the guide 410 to the steering spindle. Also shownare two wheel units 200, without the wheels 230 attached, mounted on thespindle bosses B. The bracket 520 may be a separate component that isattached to the steering spindle, as needed, or incorporated into thecasting of the spindle. If the bracket is a separate component, thespindle body 510 may have a threaded bore or other fastening means toreceive and securely fasten the bracket 520 to the body 510. In thisembodiment, the bracket 520 has at least one eye or reinforcedthrough-bore that extends from the spindle body 510 so as to enable afastening rod that extends from the first end 411 of the guide 410 to besecurely fastened to the steering spindle. The fastening means shown inthese two figures is simply illustrative of one manner of affixing theguide 410 to the spindle body 510. Other suitable fastening means may beused, such as a female threaded fastener in the spindle body and a malethreaded fastener on the guide or vice versa. It is also within thescope of the invention to integrate the guide 410 into the casting forthe steering spindle 500.

FIG. 15-18 illustrate various configurations of the steering spindle 500and the automatic deployment means 400B. FIG. 15 shows the steeringspindle 500 and the automatic deployment means 400B mounted such, thatthe cylinder 442 is mounted on a first side of the steering spindle 500and the connecting point on the cam plate 216 on the other side. Athrough-bore through the lower portion of the steering spindle 500allows the piston rod 444 to extend through the bore and be coupled withthe cam plate 212, so as to move the cam plate 212 between the stowedand deployed positions. If only a single wheel unit is mounted on thewheel-unit ready ski, an offset may be provided on the end of the rod toconnect to the cam plate. FIG. 16 illustrates the piston connectedcoupled to the cam plate, whereby the wheel unit may be mounted on thespindle or the kingpin. The piston 444 may have an offset to allow thepiston to connect to a wheel unit that is mounted on one side only ofthe wheel-unit ready ski 1000.

It is also within the scope of the invention to adapt the boss B and/ora bushing 219 to accommodate the wheel-mounting means 210. FIG. 17illustrates a bushing 219 that has been extended out beyond the boss andthe wheel unit 200 mounted on the bushing 219 and FIG. 18 shows thepiston rod 444 connected to the cam plate 212. In this embodiment, thebushing has been extended out on both ends of the kingpin 110. It isunderstood that, depending on the particular embodiment of thewheel-unit ready ski, the bushing or the boss may be extended out to oneside only. The scope of the invention is not limited to using the bossor the bushing, but rather, the wheel mounting means 210 may be adaptedto be otherwise mounted on the steering spindle 500 in a way that allowsthe wheels to be moved between the deployed and stowed positions.

FIG. 20 illustrates a combination of the steering spindle 500, theautomated deployment means 400, and the guide 420 that is integratedinto the spindle. The cylinder 442 in this embodiment is mounted in thespindle body 510. The spindle 500 and the cylinder 442 may have matingthreads as a fastening means. The cylinder 442 may also be integratedinto the casting of the spindle body 510. This embodiment shows thedistal end of the piston 442 captured in the guide 410. It may bedesirable to use the guide, rather than coupling the rod 442 directlywith the cam plate 212, as shown in other figures.

Various configurations of mounting the wheel unit 200 on a ski so thatit is balanced about the balance point of the kingpin 110 have beenshown discussed. The wheel unit has been shown mounted on a kingpin, ona steering spindle, on a side wall. Other suggested locations are on theside wall of a saddle 150. In other words, the wheel unit 200 does nothave to be mounted on the kingpin 110 or the steering spindle 500.Depending on the design of the particular ski 1000 and the configurationof wheel unit 200 and deployment unit 400, the wheel unit and deploymentunit may be mounted some distance away from the kingpin 110, in a mannerthat does not disturb the balance of the ski 1000. A counterweight mayalso be incorporated into the ski body 100 of the wheel-unit ready skito maintain the desired balance.

It is within the scope of the invention that a manufacturer providewheel openings 120 for a specific configuration of one or more wheelunits 200 for a particular snowmobile or vehicle. Thus, the wheel-unitready ski 1000 may be molded with one or more openings 120 on one sideof the ski only, or on both sides. The opening(s) may be dimensioned toaccommodate the tandem-wheel unit 200B/200C or only a single-wheel unit200A.

Different brands of ski-mounted vehicles may have special design andstructural features that would restrict the type of wheel unit 200 thatcan be incorporated into the ski 1000. It is within the scope of thisinvention to allow a ski manufacturer to configure the wheel-unit readyski 1000 to accommodate these special features. For example, if amanufacturer of a particular brand of snowmobile believes that twoone-wheel units would be appropriate for the particular snowmobile, theski may be molded with the guide 410 incorporated into one of the ribs104 and two wheel openings 120 in the ski floor 107, each wheel openingdimensioned to receive a single wheel. The manufacturer of a differenttype or brand of snowmobile or ski-mounted vehicle may recommend thatdual tandem-wheel units and the automatic deployment means 400B be usedand may then have the wheel-unit ready ski 1000 constructed accordingly.In this case, the appropriate apertures 120 are provided in the floor107 and the bracket 130 for the cylinder incorporated into the ski mold.

FIG. 19 illustrates a first embodiment of a snow guard 600, to preventsnow from flying upward. This first embodiment is a fender 600A thatpartially covers the wheel unit. The shape of the fender 600 may beconstructed to accommodate all types of wheel units described herein,or, as a design choice, the manufacturer may decide to shape the fenderto cover a specific embodiment of the wheel-unit ready ski with wheelunit. In the embodiment shown, the fender 600 is constructed to cover aninside mounted wheel unit 200A. The fender may be an integral part ofthe mold for the ski body, or may be a snap-on component that fits overthe wheel unit 200. A person of skill in the art will understand how toform a fender, whether it be intended to cover an outside- orinside-mounted wheel unit.

FIG. 21 illustrates a second embodiment of the snow guard 600 that is aflexible shield 600B that extends over the wheel opening 120 and allowsthe wheel 230 to pass through the shield 600B. When the wheel unit 200is in its stowed position, the shield 600B covers the opening and, whenin its deployed position, the shield closes around the wheel unit,effectively covering the open portion of the wheel opening 120. Examplesof suitable embodiments for the shield 600B include a brush withresilient bristles and a split flexible rubber boot.

It is understood that the embodiments described herein are merelyillustrative of the present invention. Variations in the construction ofthe ski, ski spindle, and wheel units may be contemplated by one skilledin the art without limiting the intended scope of the invention hereindisclosed and as defined by the following claims.

What is claimed is:
 1. A ski for a vehicle, the ski comprising: a skibody having a leading end and a trailing end and a longitudinal axisthat extends from the leading end to the trailing end, a floor, anunderside of which is a glide surface, and two side walls; and whereinthe ski body is adapted to receive a wheel unit, the floor of the skibody having one or more wheel openings for allowing one or more wheelson the wheel unit to move between a stowed position, in which the wheelis raised above the glide surface, and a deployed position, in which thewheel is lowered into the wheel opening to a depth lower than the glidesurface; and wherein the side walls have a reinforced section forreceiving a king pin and wherein the one or more wheel openings areprovided in a section of the floor that is near the reinforced sectionof the side walls.
 2. The ski of claim 1, wherein the one or more wheelopenings include a first and second wheel opening and the two side wallsinclude a first side wall and a second side wall, each wheel openingprovided inside the respective first and second side walls, and whereina portion of each wheel opening is situated beneath the reinforcedsection of the respective first and second side walls.
 3. The ski ofclaim 2, wherein the one or more wheel openings further include a thirdand fourth wheel opening, the third wheel opening aligned in alongitudinal direction with the first wheel opening and the fourth wheelopening similarly aligned with the second wheel opening, so as toaccommodate a wheel unit in each of the four wheel openings.
 4. The skiof claim 1, the ski body having a widening of the ski floor at least inan area of the reinforced section of the side walls.
 5. The ski of claim1, wherein the one or more wheel openings include at least a first wheelopening and a second wheel opening, the first wheel opening provided inthe ski floor outside a first side wall and the second wheel openingprovided in the ski floor outside the second side wall.
 6. The ski ofclaim 5, wherein the one or more wheel openings further include a thirdwheel opening and a fourth wheel opening, the third wheel openingaligned in a longitudinal direction with the first wheel opening and thefourth wheel opening similarly aligned with the second wheel opening. 7.A ski for a vehicle, the ski comprising: a ski body having a leading endand a trailing end and a longitudinal axis that extends from the leadingend to the trailing end, a floor, an underside of which is a glidesurface, and two side walls; and wherein the ski body is adapted toreceive a wheel unit, the floor of the ski body having one or more wheelopenings for allowing one or more wheels on the wheel unit to movebetween a stowed position, in which the wheel is raised above the glidesurface, and a deployed position, in which the wheel is lowered into thewheel opening to a depth lower than the glide surface; wherein a saddleis provided on the ski body; and wherein one of the one or more wheelopenings is provided on at least one side of the saddle.
 8. The ski ofclaim 7, wherein the saddle is a U-shaped channel having two saddle sidewalls that are adapted to receive the wheel unit.
 9. The ski of claim 8,wherein the saddle side walls replace a portion of the side walls of theski body.
 10. The ski of claim 7, wherein the saddle is an L-shapedchannel with one saddle side wall that is adapted to receive the wheelunit.
 11. The ski of claim 10, wherein the saddle side wall replaces aportion of one of the side walls on the ski body.
 12. A ski for avehicle, the ski comprising: a ski body having a leading end and atrailing end and a longitudinal axis that extends from the leading endto the trailing end, a floor, an underside of which is a glide surface,two side walls, and an inner rib; and wherein the ski body is adapted toreceive a wheel unit, the floor of the ski body having one or more wheelopenings for allowing one or more wheels on the wheel unit to movebetween a stowed position, in which the wheel is raised above the glidesurface, and a deployed position, in which the wheel is lowered into thewheel opening to a depth lower than the glide surface; and wherein theinner rib has a reinforced section and the wheel assembly is mountableon the reinforced section.
 13. A wheel-and-ski system for a ski-mountedvehicle having a ski, a steering spindle, and a kingpin to couple thesteering spindle to the ski, the system comprising: a ski that comprisesa ski body having a leading end and a trailing end and a longitudinalaxis that extends from the leading end to the trailing end, a floor, theunderside of which is a glide surface, and two side walls; a wheel unitthat is mounted inside the side walls of the ski body, the wheel unitincluding a wheel assembly and a deployment means to move the wheelassembly between a deployed position and a stowed position; wherein thewheel unit is coupled to the steering spindle.
 14. The system of claim13, wherein the wheel assembly is suspended from the kingpin and thedeployment means is coupled to the steering spindle.
 15. The system ofclaim 13, wherein the steering spindle has a through-bore for receivingthe kingpin with a boss at each end of the through-bore and the wheelassembly is suspended from the boss.
 16. The system of claim 13, whereinthe steering spindle has a through-bore for receiving the kingpin, witha bushing at each end of the through-bore, and the wheel assembly issuspended from or one or both bushings.
 17. The system of claim 14,wherein the deployment means is a manual deployment means having adeployment rail, an actuation arm that is coupled at a first end to thewheel assembly, and a capture means in the deployment rail forselectively holding a second end of the actuation arm in a deployedposition and in a stowed position; wherein the deployment rail ismounted on the steering spindle.
 18. The system of claim 17, wherein thedeployment rail is an integral part of the steering spindle.
 19. Thesystem of claim 14, wherein the deployment means is an automateddeployment means that includes a rod as an actuation arm that is coupledto the wheel unit and a cylinder that actuates the rod, and wherein thecylinder means is mounted on the ski body.
 20. The system of claim 19,wherein the cylinder is mounted on the steering spindle.
 21. The systemof claim 19, wherein the cylinder is an integral part of the steeringspindle.
 22. The system of claim 14, wherein the deployment means is asemi-automated device that includes a deployment rail, an actuation armthat is coupled at a first end to the wheel assembly, and a capturemeans in the deployment rail for selectively holding a second end of theactuation arm in a deployed position and in a stowed position, wherein abiasing spring in the actuation arm biases the deployment means to astowed position, such that, when weight is lifted from the ski, thewheel assembly automatically shifts to the stowed position.
 23. Thesystem of claim 22, wherein the deployment rail is mounted on the skibody.
 24. The system of claim 22, wherein the deployment rail is anintegral part of the molded ski body.
 25. The system of claim 22,wherein the deployment rail is mounted on the steering spindle.
 26. Thesystem of claim 14, wherein the ski body includes a saddle, and whereinthe deployment means is mounted on a sidewall of the saddle.
 27. Thesystem of claim 26, wherein the deployment means is an integral part ofthe saddle.
 28. The system of claim 13, wherein the wheel assembly ismounted on a side wall of the ski body.
 29. The system of claim 13,wherein the wheel assembly is a dual-wheel assembly having a first wheelassembly for assembling on a first side of the ski and a second wheelassembly for assembling on a second side of the ski.
 30. The system ofclaim 29, wherein the first wheel assembly and second wheel assembly areganged together with a coupling mechanism, so as to be actuatable by asingle deployment means.
 31. The system of claim 30, wherein thedual-wheel assembly includes a pair of tandem wheels that are alignedone behind the other and are ganged together so as to be actuatable by asingle deployments means.
 32. The system of claim 13, wherein the ski isadapted to receive the wheel unit, the floor of the ski body having oneor more wheel openings for allowing one or more wheels of the wheelassembly to move between a stowed position, in which the wheel is raisedabove the glide surface, and a deployed position, in which the wheel islowered into the wheel opening to a depth lower than the glide surface.33. The system of claim 32, wherein the ski body has a middle sectionthat includes a reinforced section in the sidewalls for receiving thekingpin, and wherein the floor has a wheel opening the middle section.34. The system of claim 33, wherein the wheel assembly is mounted in themiddle section such that the wheel is deployable through the wheelopening.
 35. The system of claim 33, wherein the wheel opening in themiddle section is outside of the sidewall.
 36. The system of claim 33,wherein at least the middle section is widened to accommodate the wheelopening in the floor outside of the sidewall.